In acromegaly, nearly 40% of patients fail to control GH/IGF-I levels with somatostatin analogues (SA). Dopaminergic agonists (DA) are even less effective, but combination therapy with SA and DA normalizes IGF-I levels in 33-56% of patients in short-term studies. This study was designed to evaluate short and long term efficacy of cabergoline in controlling IGF-I levels in acromegalic patients receiving octreotide.